Assessing Real-World Racial Differences Among Patients With Metastatic Triple-Negative Breast Cancer in US Community Practices

Objective

Real-world data characterizing differences between African American (AA) and White women with metastatic triple-negative breast cancer (mTNBC) are limited. Using 9 years of data collected from community practices throughout the United States, we assessed racial differences in the proportion of patients with mTNBC, and their characteristics, treatment, and overall survival (OS).

Methods

This retrospective study analyzed de-identified data from 2,116 patients with mTNBC in the Flatiron Health database (January 2011 to March 2020). Characteristics and treatment patterns between AA and White patients with mTNBC were compared using descriptive statistics. OS was examined using Kaplan-Meier analysis and a multivariate Cox proportional hazards regression model.

Results

Among patients with metastatic breast cancer, more AA patients (23%) had mTNBC than White patients (12%). This difference was particularly pronounced in patients who lived in the Northeast, were aged 45–65, had commercial insurance, and had initial diagnosis at stage II. AA patients were younger and more likely to have Medicaid. Clinical characteristics and first-line treatments were similar between AA and White patients. Unadjusted median OS (months) was shorter in AA (10.3; 95% confidence interval [CI]: 9.1, 11.7) vs. White patients (11.9; 95% CI: 10.9, 12.8) but not significantly different. After adjusting for potential confounders, the hazard ratio for OS was 1.09 (95% CI: 0.95, 1.25) for AA vs. White patients.

Conclusions

The proportion of patients with mTNBC was higher in AA than White mBC patients treated in community practices. Race did not show an association with OS. Both AA and White patients with mTNBC received similar treatments. OS was similarly poor in both groups, particularly in patients who had not received any documented anti-cancer treatment. Effective treatment remains a substantial unmet need for all patients with mTNBC.

Phase II Study of Copanlisib in Patients With Tumors With PIK3CA Mutations: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol Z1F

PURPOSE

Activating mutations in PIK3CA are observed across multiple tumor types. The NCI-MATCH (EAY131) is a tumor-agnostic platform trial that enrolls patients to targeted therapies on the basis of matching genomic alterations. Arm Z1F evaluated copanlisib, an α and δ isoform-specific phosphoinositide 3-kinase (PI3K) inhibitor, in patients with PIK3CA mutations (with or without PTEN loss).

PATIENTS AND METHODS

Patients received copanlisib (60 mg intravenous) once weekly on days 1, 8, and 15 in 28-day cycles until progression or toxicity. Patients with KRAS mutations, human epidermal growth factor receptor 2-positive breast cancers, and lymphomas were excluded. The primary end point was centrally assessed objective response rate (ORR); secondary end points included progression-free survival, 6-month progression-free survival, and overall survival.

RESULTS

Thirty-five patients were enrolled, and 25 patients were included in the primary efficacy analysis as prespecified in the Protocol. Multiple histologies were enrolled, with gynecologic (n = 6) and gastrointestinal (n = 6) being the most common. Sixty-eight percent of patients had ≥ 3 lines of prior therapy. The ORR was 16% (4 of 25, 90% CI, 6 to 33) with P = .0341 against a null rate of 5%. The most common reason for protocol discontinuation was disease progression (n = 17, 68%). Grade 3/4 toxicities observed were consistent with reported toxicities for PI3K pathway inhibition. Sixteen patients (53%) had grade 3 toxicities, and one patient (3%) had grade 4 toxicity (CTCAE v5.0). Most common toxicities include hyperglycemia (n = 19), fatigue (n = 12), diarrhea (n = 11), hypertension (n = 10), and nausea (n = 10).

CONCLUSION

The study met its primary end point with an ORR of 16% (P = .0341) with copanlisib showing clinical activity in select tumors with PIK3CA mutation in the refractory setting.

Phase II Study of Taselisib in PIK3CA-Mutated Solid Tumors Other Than Breast and Squamous Lung Cancer: Results From the NCI-MATCH ECOG-ACRIN Trial (EAY131) Subprotocol I

PURPOSE

PIK3CA mutations frequently contribute to oncogenesis in solid tumors. Taselisib, a potent and selective inhibitor of phosphoinositide 3-kinase, has demonstrated clinical activity in PIK3CA-mutant breast cancer. Whether PIK3CA mutations predict sensitivity to taselisib in other cancer types is unknown. National Cancer Institute-Molecular Analysis for Therapy Choice Arm EAY131-I is a single-arm, phase II study of the safety and efficacy of taselisib in patients with advanced cancers.

METHODS

Eligible patients had tumors with an activating PIK3CA mutation. Patients with breast or squamous cell lung carcinoma, or whose cancer had KRAS or PTEN mutations, were excluded. Patients received taselisib 4 mg, orally once daily continuously, until disease progression or unacceptable toxicity. The primary end point was objective response rate. Secondary end points included progression-free survival (PFS), 6-month PFS, overall survival (OS), and identification of predictive biomarkers.

RESULTS

Seventy patients were enrolled, and 61 were eligible and initiated protocol therapy. Types of PIK3CA mutations included helical 41 of 61 (67%), kinase 11 of 61 (18%), and other 9 of 61 (15%). With a median follow-up of 35.7 months, there were no complete or partial responses. Six-month PFS was 19.9% (90% CI, 12.0 to 29.3) and median PFS was 3.1 months (90% CI, 1.8 to 3.7). Six-month OS was 60.7% (90% CI, 49.6 to 70.0) and median OS was 7.2 months (90% CI, 5.9 to 10.0). Individual comutations were too heterogeneous to correlate with clinical outcome. Fatigue, diarrhea, nausea, and hyperglycemia were the most common toxicities, and most were grade 1 and 2.

CONCLUSION

In this study, taselisib monotherapy had very limited activity in a heterogeneous cohort of heavily pretreated cancer patients with PIK3CA-mutated tumors; the presence of a PIK3CA mutation alone does not appear to be a sufficient predictor of taselisib activity.

Personalized Nutrition as a Key Contributor to Improving Radiation Response in Breast Cancer

Understanding metabolic and immune regulation inherent to patient populations is key to improving the radiation response for our patients. To date, radiation therapy regimens are prescribed based on tumor type and stage. Patient populations who are noted to have a poor response to radiation such as those of African American descent, those who have obesity or metabolic syndrome, or senior adult oncology patients, should be considered for concurrent therapies with radiation that will improve response. Here, we explore these populations of breast cancer patients, who frequently display radiation resistance and increased mortality rates, and identify the molecular underpinnings that are, in part, responsible for the radiation response and that result in an immune-suppressive tumor microenvironment. The resulting immune phenotype is discussed to understand how antitumor immunity could be improved. Correcting nutrient deficiencies observed in these populations should be considered as a means to improve the therapeutic index of radiation therapy.

Abstract LBA003: Erdafitinib in patients with tumors harboring FGFR gene mutations or fusions: Results from the NCI-MATCH ECOG-ACRIN Trial (EAY131) Sub-protocol K2

Background: The NCI-MATCH precision medicine trial assigns patients (pts) with solid tumors, lymphoma, or multiple myeloma whose cancers have progressed on prior treatment to a targeted therapy based on genetic alterations identified in pre-treatment biopsies. Arm K2 (EAY131-K2) evaluated the pan-FGFR inhibitor erdafitinib (E) in pts with FGFR mutations or fusions. Patients and methods: Pts with bladder or urothelial cancers were excluded. Pts received E 8 mg PO daily (28-day cycle) until disease progression or unacceptable toxicity; dose reduction for toxicities was allowed; imaging was performed every 2 cycles. The primary endpoint was objective response rate (ORR); secondary endpoints included progression-free survival (PFS), 6-month PFS, and overall survival (OS). Results: A total of 35 pts were enrolled to this arm from 07/2018-07/2019; one was ineligible and one did not receive treatment. Nine distinct tumor histologies were represented, most common being pancreatobiliary (11), CNS (7) and gynecological tumors (5). 73% of pts were female, with median age of 59y (range 26-83y), 70% were Caucasian, and 61% of pts had received at least 3 prior therapies (range 0-22). Alterations in FGFR1, FGFR2 and FGFR3 were recorded in 6, 18, and 9 evaluable pts, respectively. 18 pt tumors had fusions and 15 had mutations in an FGFR gene. The confirmed ORR was 12% (90% CI 4%, 26%), with a median duration of response (DoR) of 7.3 months (mo), range 4.2-11.7 mo. Responses were seen in cholangiocarcinoma (2 pts), Brenner ovarian tumor and adenoid cystic carcinoma (1 pt each). Two (50%) of these 4 tumors harbored FGFR fusions and 2 FGFR mutations. 13 pts had stable disease (SD). Median PFS was 3.9 mo, and 6-mo PFS was 32.8% (90% CI 21.2%, 50.6%). Median OS was 11.0 mo. Of the 6 pts with intrahepatic cholangiocarcinoma, 2 had PR and 2 SD. The most frequent grade 3 treatment-related AEs were oral mucositis/pain (5 pts), paronychia, electrolyte disorders, and anemia/lymphopenia (2 pts each). There were no treatment-related grade 4-5 toxicities. Toxicities were reversible and manageable with E dose interruptions and/or dose reduction. Conclusions: In this pre-treated, mixed histology cohort with tumors harboring FGFR somatic alterations, E showed activity with durable responses and disease stabilizations outside of currently approved FDA indications, although the pre-specified criterion that the primary endpoint, ORR, be significantly greater than 16% was not reached. Toxicities were consistent with E safety profile. Responses were observed in tumors harboring FGFR fusions as well as in those with mutations of FGFR; further correlative analyses are planned.

Citation Format: Alain C Mita, Zihan Wei, Ingrid A Mayer, Heather Cheng, Edith P Mitchell, John J Wright, Percy Ivy, Robert J Gray, Victoria Wang, Lisa M McShane, Larry V Rubinstein, David R Patton, Mickey Williams, Stanley R Hamilton, Barbara A Conley, Carlos L Arteaga, Lyndsay N Harris, Peter J O'Dwyer, Alice P Chen, Keith T Flaherty. Erdafitinib in patients with tumors harboring FGFR gene mutations or fusions: Results from the NCI-MATCH ECOG-ACRIN Trial (EAY131) Sub-protocol K2 [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA003.

Establishing a Primary Care Alliance for Conducting Cancer Prevention Clinical Research at Community Sites

In September 2020, the National Cancer Institute convened the first PARTNRS Workshop as an initiative to forge partnerships between oncologists, primary care professionals, and non-oncology specialists for promoting patient accrual into cancer prevention trials. This effort is aimed at bringing about more effective accrual methods to generate decisive outcomes in cancer prevention research. The workshop convened to inspire solutions to challenges encountered during the development and implementation of cancer prevention trials. Ultimately, strategies suggested for protocol development might enhance integration of these trials into community settings where a diversity of patients might be accrued. Research Bases (cancer research organizations that develop protocols) could encourage more involvement of primary care professionals, relevant prevention specialists, and patient representatives with protocol development beginning at the concept level to improve adoptability of the trials within community facilities, and consider various incentives to primary care professionals (i.e., remuneration). Principal investigators serving as liaisons for the NCORP affiliates and sub-affiliates, might produce and maintain "Prevention Research Champions" lists of PCPs and non-oncology specialists relevant in prevention research who can attract health professionals to consider incorporating prevention research into their practices. Finally, patient advocates and community health providers might convince patients of the benefits of trial-participation and encourage "shared-decision making."

Abstract 2624: Clinical trial participation in real-world patients with metastatic breast cancer: disparities and barriers

Background: Reducing barriers to patient participation in clinical trials is vitally important to the cancer care community. Using data from a real-world cohort of metastatic breast cancer (mBC) patients (pts), we evaluated how race/ethnicity and other socioeconomic, institutional, and clinical barriers play a role in trial participation.

Methods: Adult females with mBC were selected from Flatiron Health EHR-derived de-identified database (2011- 2020). Clinical trial participation was determined by having “clinical study drug” in any line of therapy. Multivariate logistic regressions were used to assess how various barriers impact trial participation.

Results: In this cohort of 22,220 mBC pts, 1,131 (5.1%) were enrolled in clinical trials and participation rates vary by line of therapy, race/ethnicity, age, insurance, location, and care setting (Table 1). Comparing pts characteristics between enrolled vs. not enrolled, pts ever enrolled were significantly younger (mean age: 59 vs 63), had better performance status (ECOG PS ≥ 2: 3% vs 8%), and less Brain/CNS metastasis (3% vs 6%), more likely to be white (75% vs 61%), lived in the south (55% vs 38%), and had commercial insurance (34% vs 29%), with all p<0.001. Controlling for all SES and clinical characteristics that significantly differ between pts enrolled vs. not enrolled, racial/ethnic minority status remained as a strong predictor for lack of trial participation ([OR(95%CI)]: African-American(AA) [0.5(0.4-0.7)]; Hispanic: [0.6(0.4-0.8)], vs White).

Conclusions: Preliminary results of this study reveal significant demographic and socioeconomic disparities in trial participation among mBC patients. In particular, AA and Hispanic patients were less likely to participate in clinical trials after controlling for other individual- or system-level factors that may impact enrollment. Future efforts to understand the relationship between racial disparity and other well-known barriers are needed.

TABLE 1.Proportion of Patients Enrolled in Clinical Trials (N=22,220)Total, NProportion enrolled in clinical trials, n(%)Line of Therapy1L19,559435 (2.2%)2L12,627336 (2.7%)3L+7,959360 (4.5%)*Age at Diagnosis<6511,356732 (6.4%)*65 - 755,801273 (4.7%)75+5,063126 (2.5%)Race/EthnicityAfrican-American2,39597 (4.1%)Hispanic or Latino1,70251 (3.0%)Asian49420 (4.1%)White13,707851 (6.2%)*Other/Unknown3,922112 (2.9%)Geographic RegionMidwest3,062106 (3.5%)Northeast3,89476 (2.0%)South8,645618 (7.2%)*West3,998174 (4.4%)Insurance at DiagnosisCommercial6,398388 (6.1%)*Medicaid49013 (2.7%)Medicare4,232158 (3.7%)Other or Missing11,100572 (5.2%)Care SettingAcademic1,558137 (8.8%)*Community20,662994 (4.8%)Note: * denotes subgroup of patients with the highest rate of clinical trial participation

Citation Format: Ruoding Tan, Rongrong Wang, Ibrahim Abbass, Lourenia Cassoli, Edith P. Mitchell. Clinical trial participation in real-world patients with metastatic breast cancer: disparities and barriers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2624.

Differential Outcomes in Codon 12/13 and Codon 61 NRAS-Mutated Cancers in the Phase II NCI-MATCH Trial of Binimetinib in Patients with NRAS-Mutated Tumors

PURPOSE

Preclinical and clinical data suggest that downstream inhibition with an MEK inhibitor, such as binimetinib, might be efficacious for NRAS-mutated cancers.

PATIENTS AND METHODS

Patients enrolled in the NCI-MATCH trial master protocol underwent tumor biopsy and molecular profiling by targeted next-generation sequencing. Patients with NRAS-mutated tumors, except melanoma, were enrolled in subprotocol Z1A, a single-arm study evaluating binimetinib 45 mg twice daily. The primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS) and overall survival (OS). A post hoc analysis examined the association of NRAS mutation type with outcome.

RESULTS

In total, 47 eligible patients with a refractory solid tumor harboring a codon 12, 13, or 61 NRAS mutation were treated. Observed toxicity was moderate, and 30% of patients discontinued treatment because of binimetinib-associated toxicity. The ORR was 2.1% (1/47 patients). A patient with malignant ameloblastoma harboring a codon 61 NRAS mutation achieved a durable partial response (PR). A patient with NRAS codon 61-mutated colorectal cancer had an unconfirmed PR, and two other patients with NRAS codon 61-mutated colorectal had stable disease for at least 12 months. In an exploratory analysis, patients with colorectal cancer bearing a NRAS codon 61 mutation (n = 8) had a significantly longer OS (P = 0.03) and PFS (P = 0.007) than those with codon 12 or 13 mutations (n = 16).

CONCLUSIONS

Single-agent binimetinib did not show promising efficacy in NRAS-mutated cancers. The observation of increased OS and PFS in patients with codon 61 NRAS-mutated colorectal cancer merits further investigation.

A phase 2 study of defactinib (VS-6063) in patients with NF2 altered tumors: Results from NCI-match (EAY131) subprotocol U

3087

Background: The NCI-MATCH trial assigns patients (pts) with solid tumors, lymphomas, or multiple myeloma to targeted therapies based on genetic alterations identified in tumor biopsies. Neurofibromatosis 2 (NF2)-inactivated tumors demonstrate increased sensitivity to FAK inhibition in preclinical models. Arm U evaluated the FAK inhibitor defactinib in pts with NF2 altered tumors. Methods: Patients found to harbor an inactivating NF2 mutation on NGS were assigned to the ARM U substudy MATCH. Defactinib 400 mg was given by mouth twice daily until progression or intolerable toxicity. The primary endpoint was objective response rate (ORR). Secondary endpoints included toxicity, progression-free survival (PFS), and 6-month PFS. Results: Of 5,548 cases with sufficient tissue for genomic analysis, 51 pts were found to have NF2 alterations (< 1% of the total analyzed). While NF2 alterations are known to occur more commonly in meningiomas and mesotheliomas, alterations were also detected in an array of other tumor types, including renal cell carcinomas and ovarian cancers. Thirty-five pts were ultimately enrolled; 33 patients were started on therapy, with 2 of those determined to be ineligible for outcome analysis. All pts had received at least one prior therapy, with 52% (16/31) having received 3 or more prior lines of therapy. Median follow-up was 35.9 months. ORR [90% CI] was 3% (1/31, [0.16, 14.86]), with the one partial response in a pt with choroid meningioma. Of the twelve pts whose best response was stable disease (39%, 12/31), 8 demonstrated some degree of tumor shrinkage (Table) with a disease control rate of 42% (13/31). Median PFS was 1.9 months for the 31 eligible pts who received study treatment, with median PFS of 9.3 months for the 9 patients who had a best response of stable disease or better. Six pts achieved a PFS of greater than 5.5 months. Among all treated pts (n=33), the most common treatment-related toxicities were fatigue (36%), nausea (33%), and hyperbilirubinemia (27%). There were no grade 4 or 5 toxicities; 27% of pts had grade 3 toxicities. No correlation could be made between clinical outcomes and tumor histology or specific NF2 genotype. Conclusions: Defactinib monotherapy had limited clinical activity in this cohort of previously treated patients with solid tumors exhibiting NF2 loss. Clinical trial information: NCT04439331. [Table: see text]

Associations between age and stage at presentation among black and white colorectal cancer patients

e15542

Background: Blacks have a 25% higher incidence of colorectal cancer compared to their white societal counterparts. Additionally, the overall mortality rate among black colorectal cancer patients is 50% higher than that of whites. It is suggested that the etiology of this disparity may be inadequate screening for colorectal cancer among racial communities. However, little is known about the correlations between age and stage at presentation among black and white colorectal cancer patients at Thomas Jefferson University Hospital (TJUH). Objective: The objective of this study is to explore diagnostic trends that may unveil differences in age and stage at presentation between black and white colorectal cancer patients. Methods: De-identified patient data was obtained from The Oncology Data Services Department (Cancer Registry) of TJUH. The population cohort (n= 529) included newly diagnosed colorectal cancer patients treated at TJUH from 2015-2019 and included information regarding race, sex, age at presentation, stage at presentation, histological code, tumor markers: KRAS, NRAS, BRAF, MS1, treatment received, surgical findings: tumor size, lymph node involvement, presence of distant metastases at first surgery, response to chemotherapy & disease-free survival. The cohort was divided by age (<50, 50-65, >65). Patient age was compared against AJCC stage at presentation. Results: Findings reveal 12.38% of blacks & 14.29% of whites presented before age 50. 36.19% of blacks and 30.19% of whites presented between ages 50-65. 51.43% of blacks & 55.42% of whites presented after age 65. Additionally, the average age at presentation among blacks was 62.71 years vs. 65.71 years among whites. Lastly, the average stage at presentation among blacks was between 2C and 3A while the average stage at diagnosis among whites was between least 2B and 2C. Conclusions: Within this population, similarities exist among age at presentation between black and white patients, however, differences in stage at presentation exist between blacks and whites. Further research is needed explore how these findings inform the poor clinical outcomes seen among black colorectal cancer patients. Future analysis of this cohort will explore trends regarding time to treatment and treatment received after diagnosis, as similar studies have found differences among racial populations.

Prospective validation of genetic predictors of aromatase inhibitor-associated musculoskeletal symptoms (AIMSS) in a racially diverse cohort: Results from ECOG-ACRIN E1Z11

12003

Background: AIMSS are common and frequently lead to early discontinuation of adjuvant AI therapy. Single nucleotide polymorphisms (SNPs) in candidate genes have been associated with AIMSS and AI discontinuation. The primary objective of E1Z11 was to validate previously identified associations between 10 specific SNPs in candidate genes and AI discontinuation due to AIMSS in a community-based, racially diverse cohort. Methods: Postmenopausal women with hormone receptor-positive stage I-III breast cancer enrolled onto a prospective multi-site cohort study, the majority through the NCI Community Oncology Research Program (NCORP). Participants received anastrozole 1 mg oral daily, and completed patient-reported outcomes (PROs) at baseline, 3, 6, 9, and 12 months. AIMSS was defined as >20% increase in Stanford Health Assessment Questionnaire (HAQ) score over baseline occurring within 1 year of AI therapy. We projected 40% would develop AIMSS and 25% would discontinue AI treatment within 1 year, informing a planned enrollment of 1000 women with a fixed number per strata (600 Caucasian, 200 African-American [AA] & 200 Asian) to provide 80% power to detect an effect size of 1.5-4. SNPs include ESR1 (rs2234693, rs2347868, rs9340835), CYP19A1 (rs1062033, rs4646), TCL1A (rs11849538, rs2369049, rs7158782, rs7159713), and HTR2A (rs2296972). Hardy-Weinberg equilibrium (HWE) was evaluated within each racial subset. SNP genotypes were coded as additive effects on the log odds ratio by coding as 0, 1 or 2 for the count of the minor allele. A Cochran-Armitage trend test was used with a 1-sided alpha of 0.0025 (Bonferroni correction for 10 tests). Results: We enrolled 999 evaluable women (616 Caucasian, 184 AA, 199 Asian). Genotyping was successful in 974 (98%). AIMSS developed in 43%, and AI therapy was discontinued in 12% within 1 year. While more AA and Asians developed AIMSS compared to Caucasians (48% vs 38%, p=0.017; 50% vs 38%, p=0.004), AI discontinuation rates were similar across racial groups. HWE was satisfied for all SNPs at the 5% alpha level, except for TCL1A/rs11849538 (p=0.002) in the AA cohort. None of the 10 SNPs were significantly associated with AI discontinuation or development of AIMSS in the overall population, or in any of the 3 cohorts. Conclusions: Although AIMSS were more common in AA and Asians, AI discontinuation rates were similar in the 3 cohorts. We were unable to prospectively validate 10 SNPs in 4 genes previously associated with AI discontinuation due to AIMSS. Future analyses will include other predictors of AIMSS, PROs, and additional genetic markers for the entire cohort and by race. Support: NCI UG1CA189828, UG1CA233196, UG1CA233277, UG1CA233320, UG1CA233178, UG1CA233160, UG1CA232760, UG1CA233341, UG1CA233329, U10CA180821, UG1CA189821, UG1CA189830, U10CA180888, UG1CA189859, UG1CA189863, UG1CA189971. Clinical trial information: NCT01824836.

The Molecular Analysis for Therapy Choice (NCI-MATCH) Trial: Lessons for Genomic Trial Design

Background

The proportion of tumors of various histologies that may respond to drugs targeted to molecular alterations is unknown. NCI-MATCH, a collaboration between ECOG-ACRIN Cancer Research Group and the National Cancer Institute, was initiated to find efficacy signals by matching patients with refractory malignancies to treatment targeted to potential tumor molecular drivers regardless of cancer histology.

Methods

Trial development required assumptions about molecular target prevalence, accrual rates, treatment eligibility, and enrollment rates as well as consideration of logistical requirements. Central tumor profiling was performed with an investigational next-generation DNA–targeted sequencing assay of alterations in 143 genes, and protein expression of protein expression of phosphatase and tensin homolog, mutL homolog 1, mutS homolog 2, and RB transcriptional corepressor 1. Treatments were allocated with a validated computational platform (MATCHBOX). A preplanned interim analysis evaluated assumptions and feasibility in this novel trial.

Results

At interim analysis, accrual was robust, tumor biopsies were safe (<1% severe events), and profiling success was 87.3%. Actionable molecular alteration frequency met expectations, but assignment and enrollment lagged due to histology exclusions and mismatch of resources to demand. To address this lag, we revised estimates of mutation frequencies, increased screening sample size, added treatments, and improved assay throughput and efficiency (93.9% completion and 14-day turnaround).

Conclusions

The experiences in the design and implementation of the NCI-MATCH trial suggest that profiling from fresh tumor biopsies and assigning treatment can be performed efficiently in a large national network trial. The success of such trials necessitates a broad screening approach and many treatment options easily accessible to patients.

Colorectal Cancer: In the Pursuit of Health Equity

Colorectal cancer mortality has decreased considerably following the adoption of national screening programs, yet, within at-risk subgroups, there continue to be measurable differences in clinical outcomes from variations in screening, receipt of chemotherapy, radiation or surgery, access to clinical trials, research participation, and survivorship. These disparities are well-described and some have worsened over time. Disparities identified have included race and ethnicity, age (specifically young adults), socioeconomic status, insurance access, geography, and environmental exposures. In the context of the COVID-19 pandemic, colorectal cancer care has necessarily shifted dramatically, with broad, immediate uptake of telemedicine, transition to oral medications when feasible, and considerations for sequence of treatment. However, it has additionally marginalized patients with colorectal cancer with historically disparate cancer-specific outcomes; among them, uninsured, low-income, immigrant, and ethnic-minority patients-all of whom are more likely to become infected, be hospitalized, and die of either COVID-19 or colorectal cancer. Herein, we outline measurable disparities, review implemented solutions, and define strategies toward ensuring that all have a fair and just opportunity to be as healthy as possible.

Racial Disparities in Rates of Surgery for Esophageal Cancer: a Study from the National Cancer Database

BACKGROUND

Treatment guidelines for stage I-III esophageal cancer indicate that management should include surgery in appropriate patients. Variations in utilization of surgery may contribute to racial differences observed in survival. We sought to identify factors associated with racial disparities in surgical resection of esophageal cancer and evaluate associated survival differences.

METHODS

Patients diagnosed with stage I-III esophageal cancer from 2004 to 2015 were identified using the National Cancer Database. Matched patient cohorts were created to reduce confounding. Multivariate logistic regression was used to identify factors associated with receipt of surgery. Multi-level modeling was performed to control for random effects of individual hospitals on surgical utilization.

RESULTS

A total of 60,041 patients were included (4402 black; 55,639 white). After 1:1 matching, there were 5858 patients evenly distributed across race. For all stages, significantly fewer black than white patients received surgery. Black race independently conferred lower likelihood of receiving surgery in single-level multivariable analysis (OR (95% CI); stage I, 0.67 (0.48-0.94); stage II, 0.76 (0.60-0.96); stage III, 0.62 (0.50-0.76)) and after controlling for hospital random effects. Hospital-level random effects accounted for one third of the unexplained variance in receipt of surgery. Risk-adjusted 1-, 3-, and 5-year mortality was higher for patients who did not undergo surgery.

CONCLUSION

Black patients with esophageal cancer are at higher risk of mortality compared to white patients. This increased risk may be influenced by decreased likelihood of receiving surgical intervention for resectable disease, in part because of between-hospital differences. Improving access to surgical care may improve disparities in esophageal cancer survival.

Abstract PS7-53: Assessing racial differences in patients with metastatic triple-negative breast cancer: Real-world evidence from US community oncology practices

Background: Metastatic triple-negative breast cancer (mTNBC) is an aggressive tumor phenotype with a poor prognosis and few treatment options. The prevalence of mTNBC is disproportionately higher among African American (AA) women, compared with white women. Data identifying the drivers of racial differences in mTNBC or characterizations of treatment patterns and clinical outcomes in AA patients with mTNBC are limited. Methods: This retrospective study used the Flatiron Health electronic health record-derived de-identified database (January 2011-March 2020). Adult AA and white female patients with confirmed mTNBC treated in US community oncology practices were included. Differences in mTNBC prevalence among AA and white patients were assessed by age, health insurance coverage, geographic region and stage at initial diagnosis. Descriptive statistics were used to analyze clinical characteristics, treatment patterns and time to treatment initiation between AA and white patients. Racial differences in overall survival (OS) were examined using Kaplan-Meir analysis and a multivariate Cox regression model. Results: Of the 21,804 Flatiron patients diagnosed with metastatic breast cancer (mBC), 2116 eligible patients with mTNBC were identified; 383 (18%) were AA and 1155 (55%) were white. TNBC prevalence was twice as high among AA patients (23%) than white patients (12%). Racial differences in TNBC prevalence (AA vs white patients) were particularly higher among patients aged 45 to 65 y (26% vs 13%), patients in the Northeast (27% vs 11%) and those with initial diagnosis at Stage II (30% vs 13%) or Stage III (27% vs 15%). AA patients with TNBC were younger (mean age: 60 vs 63 y; P &lt; 0.001) and more likely to have Medicaid at the time of diagnosis (10% vs 3%; P &lt; 0.001) than white patients. Clinical characteristics were generally similar between AA and white patients, including the distribution of staging at initial diagnosis, disease recurrence, Eastern Cooperative Oncology Group performance status (ECOG PS), and sites and number of metastases. Regardless of race, 25% of all patients with mTNBC had no documentation of receiving anti-cancer treatment in the database. Untreated patients in both race groups were older, had poorer ECOG PS and were less likely to have visceral metastases than treated patients (all P &lt; 0.001); they also had poorer survival than treated patients (median OS: 4.7 vs 13.1 months from diagnosis for all treated patients; unadjusted hazard ratio [HR], 0.51 [95% CI: 0.46, 0.57]). Among both AA and white treated patients, single-agent chemotherapy was the most prevalent first-line treatment (most common agent: capecitabine). More than half of treated patients initiated treatment in &lt; 30 days, and median time-to-treatment initiation did not differ by race. Although OS was numerically lower in AA patients (median OS, 10.3 vs 11.9 months in white patients), the difference was not significant when adjusted for prognostic and treatment factors (adjusted HR, 1.09 [95% CI: 0.95, 1.25]). Conclusions: The prevalence of mTNBC was twice as high among AA compared with white patients in US community oncology practices. Unlike prior research, race did not show an association with OS in this population. Regardless of race, 1 in every 4 patients with mTNBC had not received documented anti-cancer treatment, potentially due to poor PS and concerns about treatment tolerance. OS was poor for both AA and white patients with mTNBC, particularly for untreated patients. Effective treatment remains a substantial unmet need for all patients with mTNBC. In light of the lack of racial differences in this patient cohort, prospective studies are needed to further elucidate underlying biological differences that may have predictive or prognostic significance for AA patients with TNBC.

Citation Format: Amie Tan, Vincent Shen, Luciana Preger, Bann-mo Day, Edith P. Mitchell. Assessing racial differences in patients with metastatic triple-negative breast cancer: Real-world evidence from US community oncology practices [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-53.

Status of the Clinician Investigator in America: An Essential Healthcare Provider Driving Advances in Cancer Care

BACKGROUND

Translation of basic discoveries to clinical care for patients with cancer is a difficult process greatly enabled by physician-trained researchers. Three categories of physicians, with responsibilities spanning from laboratory and preclinical research to direct patient care, are involved in the translational research continuum: physician-scientist (PS), clinician investigator (CI), and academic clinician (AC).

METHODS

To define how protected time for research efforts is supported, the Association of American Cancer Institutes (AACI) conducted a survey of their member institutions, obtaining 56 responses documenting time spent in research and clinical activities across multiple cancer disciplines, and providing information about funding streams for the different categories of cancer physicians.

RESULTS

Responses showed that PSs and ACs are minimally involved in clinical research activities; the driver or clinical research in academic cancer centers is the CI. A significant concern was a lack of stable funding streams for nonbillable clinical research activities, putting the sustainability of the CI in jeopardy. Limited funding was derived from hospital sources, with most support derived from cancer center sources.

CONCLUSIONS

This study highlights the importance of the CI in translational cancer medicine and represents a call to action for institutions and research funding agencies to develop new programs targeted toward CI support to ensure continued progress against cancer.

Effect of Capivasertib in Patients With an AKT1 E17K-Mutated Tumor: NCI-MATCH Subprotocol EAY131-Y Nonrandomized Trial

Importance

In the National Cancer Institute Molecular Analysis for Therapy Choice (NCI-MATCH) trial, agents targeting genetic tumor abnormalities are administered to patients. In the NCI-MATCH subprotocol EAY131-Y trial, patients with an AKT1 E17K-mutated metastatic tumor received the pan-AKT inhibitor capivasertib.

Objective

To assess the objective response rate (ORR) of capivasertib in patients with an AKT1 E17K-mutated tumor.

Design, Setting, and Participants

Between July 13, 2016, and August 10, 2017, patients in the NCI-MATCH trial were enrolled and assigned to the subprotocol EAY131-Y nonrandomized trial. Patients included adults with an AKT1 E17K-mutated metastatic tumor that had progressed with standard treatment, and these patients were assigned to receive capivasertib. Tumor assessments were repeated every 2 cycles. Data analysis of this evaluable population was performed from November 8, 2019, to March 12, 2020.

Interventions

The study treatment was capivasertib, 480 mg, orally twice daily for 4 days on and 3 days off weekly in 28-day cycles until disease progression or unacceptable toxic effect. If patients continued hormone therapy for metastatic breast cancer, the capivasertib dose was 400 mg.

Main Outcomes and Measures

The primary end point was the ORR (ie, complete response [CR] and partial response) according to the Response Evaluation Criteria in Solid Tumors criteria, version 1.1. Secondary end points included progression-free survival (PFS), 6-month PFS, overall survival, and safety.

Results

In total, 35 evaluable and analyzable patients were included, of whom 30 were women (86%), and the median (range) age was 61 (32-73) years. The most prevalent cancers were breast (18 [51%]), including 15 patients with hormone receptor (HR)-positive/ERBB2-negative and 3 with triple-negative disease, and gynecologic (11 [31%]) cancers. The ORR rate was 28.6% (95% CI, 15%-46%). One patient with endometrioid endometrial adenocarcinoma achieved a CR and remained on therapy at 35.6 months. Patients with confirmed partial response had the following tumor types: 7 had HR-positive/ERBB2-negative breast cancer, 1 had uterine leiomyosarcoma, and 1 had oncocytic parotid gland carcinoma and continued receiving treatment at 28.8 months. Sixteen patients (46%) had stable disease as the best response, 2 (6%) had progressive disease, and 7 (20%) were not evaluable. With a median follow-up of 28.4 months, the overall 6-month PFS rate was 50% (95% CI, 35%-71%). Capivasertib was discontinued because of adverse events in 11 of 35 patients (31%). Grade 3 treatment-related adverse events included hyperglycemia (8 [23%]) and rash (4 [11%]). One grade 4 hyperglycemic adverse event was reported.

Conclusions and Relevance

This nonrandomized trial found that, in patients with an AKT1 E17K-mutated tumor treated with capivasertib, a clinically significant ORR was achieved, including 1 CR. Clinically meaningful activity with single-agent capivasertib was demonstrated in refractory malignant neoplasms, including rare cancers.

Trial Registration

ClinicalTrials.gov Identifier: NCT00700882.

Abstract PO-068: Survey of healthcare providers in the ECOG-ACRIN cancer research group: Attitudes, knowledge, and practice behaviors about LGBTQ patients with cancer

INTRODUCTION: The lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ) community is a medically underserved population that suffers from cancer disparities. To identify potential gaps in attitudes, knowledge, and institutional practices toward LGBTQ patients, we conducted a mixed-methods survey of healthcare providers in the ECOG-ACRIN Cancer Research Group. METHODS: A validated, web-based survey was administered to members of the ECOG-ACRIN Cancer Research Group in late 2019. The survey was completed by 490 healthcare providers measuring attitudes and knowledge about LGBTQ health and institutional practices regarding collection of sexual orientation and gender identity data. Results were quantified using descriptive and stratified analyses. RESULTS: Among the 490 healthcare providers that completed the survey, 77% were White, 86% were non- Hispanic, 75% were female, 81% were heterosexual, and the mean age was 46 years. Approximately 47% of the respondents were medical oncologists, 39% practiced in academic medical centers (AMCs), and 49% were from the Midwest/Northeast. As reported by prior institutional and national survey studies, there was high interest (77%) in receiving education regarding the unique health needs of LGBTQ patients, an overall limited knowledge about LGBTQ health and cancer needs, and a significant decrease from survey assessment to postsurvey assessment for confidence in knowledge for LGBT health needs. There was high agreement (71%) regarding the importance of knowing gender identity, which was contrasted with a low agreement (48%) regarding the importance of knowing sexual orientation. Stratified analyses revealed significant differences of some attitude and knowledge items. For example, when stratified by licensure/terminal degree, MD/DO vs. RN/NP/PA were significantly more willing to be listed as a LGBTQ-friendly provider (81% vs. 50%) and reported to be knowledgeable about LGB health needs (69% vs. 53%). Providers at AMCs were significantly more willing to be listed as a LGBTQ-friendly provider (71% vs.53%) believe there should be mandatory education (72% vs. 60%) regarding care of LGBQ patients versus those at non-AMCs. Having family and/or friends who are LGBTQ (vs. none) and political affiliation (conservative vs. liberal) were strong effect modifiers resulting in significant differences for 9 and 8 items, respectively.

CONCLUSION: To our knowledge, this was the first study of cancer care providers in a large cancer clinical trials research group that assessed attitudes, knowledge, and institutional practices of LGBTQ patients with cancer. Consistent with prior studies, there was limited knowledge about LGBTQ health and cancer needs, but high interest in receiving education regarding this community. New and intriguing differences for many attitude and knowledge items were revealed when we stratified the responses by licensure/terminal degree, practice setting, LGBTQ friends and/or family members, and political affiliation.

Citation Format: Matthew B. Schabath, Jaileene Perez-Morales, Megan Sutter, Lynne Wagner, Melissa Simon, Ruth C. Carlos, Bruce J. Giantonio, Gwendolyn P. Quinn, Edith P. Mitchell. Survey of healthcare providers in the ECOG-ACRIN cancer research group: Attitudes, knowledge, and practice behaviors about LGBTQ patients with cancer [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-068.

Abstract PO-013: Qualitative results to a survey of ECOG-ACRIN members regarding experience with sexual and gender minority patients with cancer

Background: While societal acceptance for sexual and gender minority (SGM/LGBTQ) individuals is increasing, this population continues to face health care barriers. In addition to encountering stigmatization, SGM/LGBTQ patients are an understudied population, particularly within oncology. Little is known about clinicians’ knowledge and practice behaviors regarding SGM in the oncology setting. To address this lack of knowledge, a mixed method survey was administered to members of the ECOG- ACRIN Cancer Research Group in late 2019. Methods: In this analysis, we report on results of the qualitative portion of the survey. Four open-ended questions asked healthcare providers (i.e., oncology physicians, researchers, physician assistants, and nurses) to describe experiences with SGM patients, reservations in caring for SGM patients, suggestions for improvement in SGM cancer care, and any additional comments. Responses were organized in spreadsheet and content analysis was used to group a priori and emergent themes. Results: 490 people responded to the quantitative survey and 365 provided responses to the open-ended questions. In the personal experience question, the majority noted they had no or little familiarity with SGM patients. A minority of respondents noted experience with gay and lesbian patients with cancer, but not transgender patients; many who reported experience with transgender patients noted difficulty navigating the correct use of pronouns. In the reservations question, the majority stated they had no reservations treating SGM patients but lacked training. Suggestions for improvement included providing training in the care of SGM patients with cancer, ensuring training occurred throughout the institution and not only among clinicians, need to attend to unique end-of-life care issues among SGM patients, and need to build trust. A minority of respondents described SGM patients with cancer as difficult to treat and non- compliant. Many respondents endorsed a fear of offending patients due to general lack of knowledge or saying the wrong thing. Additional comments offered related to lack of knowledge about potential interactions between cancer treatment and gender-affirming hormones, and lesbian women’s frustrations with requirements of pregnancy testing. Conclusions: Clinicians have minimal experiences and/or exposure to SGM patients with cancer but desire training. Training the entire workforce may improve trust with, outreach efforts to, and cancer care delivery to the SGM community.

Citation Format: Christina L. Tamargo, Edith P. Mitchell, Lynne I. Wagner, Melissa A. Simon, Ruth C. Carlos, Bruce J. Giantonio, Gwendolyn P. Quinn, Matthew B. Schabath. Qualitative results to a survey of ECOG-ACRIN members regarding experience with sexual and gender minority patients with cancer [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-013.

Molecular Landscape and Actionable Alterations in a Genomically Guided Cancer Clinical Trial: National Cancer Institute Molecular Analysis for Therapy Choice (NCI-MATCH)

Therapeutically actionable molecular alterations are widely distributed across cancer types. The National Cancer Institute Molecular Analysis for Therapy Choice (NCI-MATCH) trial was designed to evaluate targeted therapy antitumor activity in underexplored cancer types. Tumor biopsy specimens were analyzed centrally with next-generation sequencing (NGS) in a master screening protocol. Patients with a tumor molecular alteration addressed by a targeted treatment lacking established efficacy in that tumor type were assigned to 1 of 30 treatments in parallel, single-arm, phase II subprotocols.